I've had them for just over a year and they were about 2 inches when I got them? Maybe thats 6 months old (assuming the LFS wasn't that clean which it usually isn't, well this one anyways) and the male is beginning to act up more recently. Any foods they like or music besides Barry White?
Wow, they sure did grow fast for you. They appear to be reaching breeding size if not age. Mine really like krill, i get freeze dried krill and soak it in water for a few minutes then dump it in. That is really the only time i ever see them feed in a aggressive manner unless chasing some peacock fry LOL.